While author William Gurstelle might use the word "castle" figuratively in his how-to book's title, he definitely means us to take the "defending" part at face value. The manual's full title is Defending Your Castle: Build Catapults, Crossbows, Moats, Bulletproof Shields, and More Defensive Devices to Fend Off the Invading Hordes. It's a mouthful. A mouthful that's chock full of instructions on how to build a garage full of ancient artillery and fortifications. So even if your castle is more like a 1,500-square-foot rambler, you'll be able to guard it against pillagers, scroungers, solicitors, and your neighbor's fat cat Willard like the 21st century knight that you are.

Gurstelle himself is an engineer, and previous author of another bestseller, Backyard Ballistics. In Defending your castle he divides and conquers the likes of Attila and the Huns, Ragnar and the Vikings, Alexander and the Greeks, Genghis Khan and the Mongols, and Tamerlane and the Tartars by chapter. In each he introduces a new motley crew, detailing their conquests, and describing their weapons and fortresses for you to build for yourself. Step-by-step instructions, diagrams, and photographs explain how to develop a dozen different replicas, from tabletop models of the Cheval-de-frise, Da Vinci's Catapult, and Alexander's Tortoise, to a full-size, functional Carpini's Crossbow, Hour-Glass Watchtower, and Palisade Wall. Troubleshooting tips and tips on where to find the best materials are also included.

Gurstelle's publishers would also like to emphasize that Defending your castle takes safety into special consideration, and hopes those using the guide to go all medieval on any punk who threatens their hearth and home will too.